Abstract:

I will describe a scanning microscope to monitor `live' the quantum dynamics of cold atoms in a cavity QED setup [1,2]. The microscope measures atomic spatial densities with subwavelength resolution via dispersive couplings to a cavity and homodyne detection within the framework of continuous measurement theory. Remarkably, in the good cavity limit, the microscope becomes an effective quantum nondemolition (QND) device, such that the spatial distribution of motional eigenstates can be measured backaction free in single scans, as an emergent QND measurement. 

[1] D. Yang et al., PRL 120, 133601 (2018)

[2] D. Yang et al., PRA 98, 023852 (2018)